One of the injured was Oleksandr Turchynov, one of the opposition leaders, who was hit by shrapnel but says "he's okay."

The police tried to storm Independence Square, aka Maidan, where activists have been camping out and protesting en masse since early December. Opposition leader Vitaly Klitschko remained defiant, telling supporters, "we will not leave here. This is an island of freedom. We will defend it," according to Reuters.

The Russian-backed forces loyal to Ukraine President Viktor Yanukovych were met with barrages of Molotov cocktails. Part of the encampment was engulfed in flames.

Previously, police had gathered around the square and clashed with protesters, but this time seemed to be a more assertive effort. Earlier police asked women and children to leave Maidan so they can begin an "anti-terrorist operation."

REUTERS/Andrew KravchenkoA boy walks by a truck on fire during clashes between anti-government protesters and Interior Ministry members in Kiev February 18, 2014. Several thousand anti-government protesters clashed with police near Ukraine's parliament on Tuesday, torching vehicles and hurling stones in the worst violence to rock the capital Kiev in more than three weeks.

Earlier the Ukrainian Berkut, the feared security apparatus of the state, gave protesters until 18:00 [11:00 EST] to end the demonstrations or face "tough measures." In response, the Right Sector, a radical far-right group, has called on protestors to start arming themselves.

The protests have become a struggle for the direction of the country and whether it stays within Moscow's orbit or moves toward integration with the EU.

Below is a video showing the pandemonium that took place earlier:

REUTERS//Vlad SodelWounded people are seen after clashes with riot police in central Kiev February 18, 2014.